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Related papers: Testing Helioseismic-Holography Inversions for Sup…

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We suggest a method that evaluates the horizontal velocity in the solar photosphere with easily observable values using a combination of neural network and radiative magnetohydrodynamics simulations. All three-component velocities of…

Solar and Stellar Astrophysics · Physics 2023-09-06 Hiroyuki Masaki , Hideyuki Hotta , Yukio Katsukawa , Ryohtaroh T. Ishikawa

A coarse-graining framework is implemented to analyze nonlinear processes, measure energy transfer rates and map out the energy pathways from simulated global ocean data. Traditional tools to measure the energy cascade from turbulence…

Fluid Dynamics · Physics 2018-02-14 Hussein Aluie , Matthew Hecht , Geoffrey K. Vallis

Accurate simulations of flows in stellar interiors are crucial to improving our understanding of stellar structure and evolution. Because the typically slow flows are merely tiny perturbations on top of a close balance between gravity and…

Solar and Stellar Astrophysics · Physics 2021-08-18 P. V. F. Edelmann , L. Horst , J. P. Berberich , R. Andrassy , J. Higl , G. Leidi , C. Klingenberg , F. K. Roepke

Acoustic holographic lenses, also known as acoustic holograms, can change the phase of a transmitted wavefront in order to shape and construct complex ultrasound pressure fields, often for focusing the acoustic energy on a target region.…

We have obtained ultra-high quality spectra (R=180,000; S/N>300) with unprecedented wavelength coverage (4400 to 7400 A) for a number of stars covering most of the HR diagram in order to test the predictions of models of stellar surface…

Solar and Stellar Astrophysics · Physics 2009-09-01 I. Ramirez , C. Allende Prieto , D. L. Lambert , L. Koesterke , M. Asplund

The performance of deep learning models in remote sensing (RS) strongly depends on the availability of high-quality labeled data. However, collecting large-scale annotations is costly and time-consuming, while vast amounts of unlabeled…

Computer Vision and Pattern Recognition · Computer Science 2025-12-02 Wei Huang , Zhitong Xiong , Chenying Liu , Xiao Xiang Zhu

Granular materials subjected to impact loading exhibit highly heterogeneous spatiotemporal dynamics governed by wave propagation, pore collapse, and grain-scale rearrangements. Mesoscale hydrocodes resolve these processes but are…

Computational Physics · Physics 2026-01-23 Kathleen Winona Vian Martinus , Sushan Nakarmi , Dawa Seo , Nitin Pandurang Daphalapurkar

In this work we present a novel methodology that combines Higher Order Singular Value Decomposition (HOSVD) with Deep Learning (DL) techniques for super-resolution in computational fluid dynamics (CFD) and sparse experimental datasets. This…

We present an efficient method for two dimensional inversions for the solar rotation rate using the Subtractive Optimally Localized Averages (SOLA) method and a modification of the R1 X R1 technique proposed by Sekii (1993). The SOLA method…

Astrophysics · Physics 2015-06-24 F. P. Pijpers , M. J. Thompson

Horizon Run 5 (HR5) is a cosmological hydrodynamical simulation which captures the properties of the Universe on a Gpc scale while achieving a resolution of 1kpc. Inside the simulation box we zoom-in on a high-resolution cuboid region with…

Below 1 mHz, the power spectrum of helioseismic velocity measurements is dominated by the spectrum of convective motions (granulation and supergranulation) making it difficult to detect the low-order acoustic modes and the gravity modes. We…

Astrophysics · Physics 2008-10-31 S. Lefebvre , R. A. Garcia , S. J. Jimenez-Reyes , S. Turck-Chieze , S. Mathur

Context. It has been suggested that convection in Red Supergiant (RSG) stars gives rise to large-scale granules causing observable surface inhomogeneities. This convection is also extremely vigorous, and suspected to be one of the causes of…

Solar and Stellar Astrophysics · Physics 2015-05-13 A. Chiavassa , B. Plez , E. Josselin , B. Freytag

Accurate simulation of turbulent flows remains a challenge due to the high computational cost of direct numerical simulations (DNS) and the limitations of traditional turbulence models. This paper explores a novel approach to augmenting…

Fluid Dynamics · Physics 2025-02-17 Jonas Luther , Patrick Jenny

Solar limb observations sometimes reveal the presence of a satellite lobe in the blue wing of the Stokes I profile from pixels belonging to granules. The presence of this satellite lobe has been associated in the past to strong line of…

Solar and Stellar Astrophysics · Physics 2016-01-18 C. Quintero Noda , T. Shimizu , Y. Suematsu

Full-disk observations from missions such as the SDO and SOHO have enabled comprehensive studies of solar oscillations and dynamics. Interpreting helioseismic and photospheric data is complicated by systematic center-to-limb variations. To…

Solar and Stellar Astrophysics · Physics 2026-04-06 Irina N. Kitiashvili

Realistic ab-initio 3D, radiative-hydrodynamical convection simulations of the solar granulation have been applied to FeI and FeII line formation. In contrast to classical analyses based on hydrostatic 1D model atmospheres the procedure…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , C. Allende Prieto , R. F. Stein

Helioseismology is the branch of the Solar Physics which studies the solar global oscillations, a phenomenon very important in order to understand the inside of the Sun. We explain here a method for measuring the solar velocity fields along…

Astrophysics · Physics 2007-05-23 I. Formicola , A. Longobardo , C. Pinto , P. Cerulo

Aims. Recent studies showed that time--distance inversions for flows start to be dominated by a random noise at a depth of only a few Mm. It was proposed that the ensemble averaging might be a solution to learn about the structure of the…

Solar and Stellar Astrophysics · Physics 2015-03-11 Michal Švanda

Helioseismic signatures of dynamo waves have recently been discovered in variations of the solar differential rotation, offering valuable insights into the type of dynamo mechanism operating in the solar convection zone. To characterize…

Solar and Stellar Astrophysics · Physics 2025-05-19 Krishnendu Mandal , Alexander G. Kosovichev , Valery V. Pipin , Sylvain G. Korzennik

Detection of a gravitational-wave stochastic background via ground or space-based gravitational-wave detectors requires the cross-correlation of the response of two or more independent detectors. The cross-correlation involves a…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Lee Samuel Finn , Shane L. Larson , Joseph D. Romano